Hello, Do you have a ticket opened for the issue with Fortinet TAC?
Google Playstore does a thing called "Certificate Pinning" which pins the public key of their SSL Certificate to the application itself. The application will do a check on the certificate and if it sees that Fortigate has resigned the original certificate, it will break the session. That is the reason it does not work. We usually have a list of domains we exempt in the SSL Certificate sensor which we know has been known to be used by applications that have Certificate Pinning.
As per a few of the other customers Fixed the issue. by adding *.googlevideo.com in the Certificate Name. Have to add it to the exempted addresses (by creating a new wildcard address) and it should work.
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